solarken
NABCEP PVIP
- Location
- Hudson, OH, USA
- Occupation
- Solar Design and Installation Professional
I am adding SolarEdge batteries and Backup Interface (BUI, a Microgrid Interconnection Device (MID)) to an existing SolarEdge PV System and would like help clarifying a few things. The existing system has a 200A meter-main on the outside of an outbuilding, and the meter-main has a 100A breaker in it that feeds a subpanel inside the outbuilding, and the feed-thru lugs in the meter main feed an underground feeder to the main home about 100ft away, via 4/0 XHHW for L1 and L2 and I believe 2/0 Neutral. There is no EGC with the feeder to the house. There is a 200A loadcenter in the home. The breaker in the meter-main was downsized to 150A and a 60A backfed PV breaker was added in the initial PV installation. The inverter is inside the outbuilding.
I am planning on installing the SolarEdge batteries and the BUI inside the outbuilding, removing the house feeder connection from the feed thru lugs, and feeding the main breaker of the BUI from the feed-thru lugs of the meter main. I will run 4/0 AL XHHW from the lugs to the BUI, with a 2/0 AL Neutral and #4 copper EGC. I plan on removing the PV breaker from the meter main and relocating the connection to the PV breaker in the BUI. I plan on pulling the disconnected house feeder into a junction box inside the outbuilding, and extending the conductors to the load terminals on the BUI.
My first question concerns the 4/0 aluminum conductors, and whether there is any violation concerning ampacity, and if 310.12 permitting 83% covers the above approach and allows 4/0 AL for the 200A. I would think this is ok, especially since the main braker in the meter main was downsized to 150A.
One issue I have with the above is that the outbuilding that will house the batteries would not have power in an outage, since the 100A subpanel is fed upstream from the meter-main, before the BUI. In Ohio, our winters can get cold, so I am thinking it might be better to replace the 100A subpanel in the outbuilding with a 200A subpanel, and feed it from the BUI load terminals, and feed the house from feed-thru terminals in this new subpanel, so everything is backed up. This would permit a small heater to be powered in the battery room during a grid outage if needed.
Is there any issue if this 200A subpanel were added, again in regards to ampacity and 310.12? And since the downsizing of the meter-main breaker from 200A to 150A was done to accommodate the PV breaker and that is no longer needed, any issue with putting back in the original 200A main breaker?
I am also going to try (finally) to use a generator connected to the generator input on the BUI. Hopefully it will work.
Your feedback and suggestions are appreciated.
I am planning on installing the SolarEdge batteries and the BUI inside the outbuilding, removing the house feeder connection from the feed thru lugs, and feeding the main breaker of the BUI from the feed-thru lugs of the meter main. I will run 4/0 AL XHHW from the lugs to the BUI, with a 2/0 AL Neutral and #4 copper EGC. I plan on removing the PV breaker from the meter main and relocating the connection to the PV breaker in the BUI. I plan on pulling the disconnected house feeder into a junction box inside the outbuilding, and extending the conductors to the load terminals on the BUI.
My first question concerns the 4/0 aluminum conductors, and whether there is any violation concerning ampacity, and if 310.12 permitting 83% covers the above approach and allows 4/0 AL for the 200A. I would think this is ok, especially since the main braker in the meter main was downsized to 150A.
One issue I have with the above is that the outbuilding that will house the batteries would not have power in an outage, since the 100A subpanel is fed upstream from the meter-main, before the BUI. In Ohio, our winters can get cold, so I am thinking it might be better to replace the 100A subpanel in the outbuilding with a 200A subpanel, and feed it from the BUI load terminals, and feed the house from feed-thru terminals in this new subpanel, so everything is backed up. This would permit a small heater to be powered in the battery room during a grid outage if needed.
Is there any issue if this 200A subpanel were added, again in regards to ampacity and 310.12? And since the downsizing of the meter-main breaker from 200A to 150A was done to accommodate the PV breaker and that is no longer needed, any issue with putting back in the original 200A main breaker?
I am also going to try (finally) to use a generator connected to the generator input on the BUI. Hopefully it will work.
Your feedback and suggestions are appreciated.